Device for delivering sheets

ABSTRACT

A device for forming a space between groups of a predetermined number of overlapped sheets moving successively in a line. The device has a first conveyor for conveying sheets of a fixed length which are cut from a band sheet. A second conveyor is provided just beyond the delivery end of the first conveyor for receiving sheets from the first conveyor in overlapping relationship. A suction means is provided adjacent said second conveyor for temporarily holding a sheet on the second conveyor by suction. The second conveyor is movable in such a way that the upper run thereof is movable up and down above and below the level of the suction means. The second conveyor is normally above the suction means, but when a predetermined number of sheets has been delivered to the second conveyor, the second conveyor is lowered, and one of the sheets delivered thereto is held by suction from the suction means to delay its movement along the second conveyor momentarily, after which the second conveyor is again raised to release the delayed sheet from the suction means.

United States Patent [1 1 Sawada i 3,791,269 Feb. 12, 1974 DEVICE FORDELIVERING SHEETS [75] inventor:

[73] Assignee: Rengo Kabushiki Kaisha (Rengo Co., Ltd.), Osaka, Japan[22] Filed: June 1, 1972 [21] Appl. No.: 258,784

Tetsuya Sawada, Kyoto, Japan [52] US. Cl. 93/93 DP, 93/93 C, 271/46,271/183, 271/202 [51] Int. Cl B65h 29/66 [58] Field oi Search 271/46,76, DIG. 8, 74, 75, 271/47, 32; 93/93 C, 93 DP Primary Examiner-Even C.Blunk Assistant ExaminerBruce H. Stone, Jr. Attorney, Agent, orFirm-Wenderoth, Lind & Ponack 7] ABSTRACT I A device for forming a spacebetween groups of a predetermined number of overlapped sheets movingsuccessively in a line. The device has a first conveyor for conveyingsheets of a fixed length which are cut from a band sheet. A secondconveyor is provided just beyond the delivery end of the first conveyorfor receiving sheets from the first conveyor in overlappingrelationship. A suction means is provided adjacent said second conveyorfor temporarily holding a sheet on the second conveyor by suction. Thesecond conveyor is movable in such a way that the upper run thereof ismovable up and down above and below the level of the suction means. Thesecond conveyor is normally above the suction means, but when apredetermined number of sheets has been delivered to the secondconveyor, the second conveyor is lowered, and one of the sheetsdelivered thereto is held by suction from the suction means to delay itsmovement along the second conveyor momentarily, after which the secondconveyor is again raised to release the delayed sheet from the suctionmeans.

1 Claim, 5 Drawing Figures PATENTED FEB 1 2 1974 SHEU10F4 DEVICE FORDELIVERING SHEETS The present invention relates to a conveyor devicewhich creates a space in an overlapping stream of sheets on a deliveryconveyor.

In a conventional method of producing a batch of cut sheets, a bandsheet is cut into sheets of a fixed length by a cutting machine and theyare carried to a belt conveyor through a sandwich conveyor. Since thespeed of the sandwich conveyor is adapted to be slightly faster than thefeeding speed of the band sheet, a space is created between the back endof the cut sheets and the front end of the band sheet. In other words, aspace is left between successive sheets. The belt conveyor is operatedat about half the feeding speed of the band sheet. Thus the cut sheetsare carried on the belt con veyor in an overlapping relationship. 7

Furthermore, a gate is provided on the carrying face of the conveyor atthe end thereof. The gate is adapted to close when the number of cutsheets is detected to be equal to a predetermined number by means of adetecting means, and the closed gate contacts the front edge of thefollowing sheet and accumulates the sheets in piles on the belt conveyorfor a fixed period until the gate again opens. When the gate is openedthe conveyor carries the next batch of cut sheets and this operation isrepeated. Thus some of the cut sheets carried by the belt conveyor inoverlapped state are held back by the gate to make a space between thepreceeding sheet and thus produce a batch of sheets consisting of theprescribed number.

However, in closing the gate after detecting that the prescribed numberof sheets have passed through, the closed gate abutting the carryingbelt produces resistance to the movement of the conveyor belt, andcauses slipping between the belts of the conveyor and the drivingpulleys, and the position of the front end of the gate relative to thefront end of the sheet changes, depending on the cutting length of thesheet and the carrying speed. Accordingly, a batch of sheets released bythe gate is not always uniform in number, and thus this system has thedisadvantage that a batch may have more or less than the prescribednumber of sheets in a batch.

An object of the present invention is to provide a device fortemporarily halting sheets on a carrying run by providing a suction boxon the under side of the carrier belt of a conveyor which positivelyretains a sheet passing thereover by suction to make batches of anyprescribed number of sheets from a flow of successively overlappingsheets carried by the conveyor.

This and other objects are accomplished by the parts, improvements,combinations and arrangements comprising the invention, a preferredembodiment of which is shown by way of example in the accompanyingdrawings, and hereinafter described in detail.

FIG. 1 is a schematic side view of a carrying apparatus.

FIG. 2 is a side view showing the essential parts thereof.

FIG. 3 is a'longitudinal sectional side view thereof.

FIG. 4 is a plane view showing a part of the suction apparatus.

FIG. 5 is a partially sectioned perspective view thereof.

Referring now to FlGS. l to 5, a cutting means B which cuts a band sheetor web A into sheets a of fixed length comprises a pair of upper andlower rolls ll, 12

which are driven at equal speeds in counterclockwise and clockwisedirections respectively, and a cutting edge 13 axially provided on theperiphery of lower roll 12. A projecting member 14 is provided on theperiphery of the projecting shaft of the upper roll 11. An actuator 17of a counter 16 is adapted to contact the projecting member 14 once perrevolution of the upper roll 11 actuating the counter to count cutsheets.

A sandwich conveyor C is located in front of the cutting means B, and aplurality of parallel endless belts 18, whose ends are respectivelysupported by means of front and rear pulleys 19, are provided oppositethe cutting means so that the carrying faces of the belts 18 may deliverthe sheets a forwards, the speed of the sandwich conveyor C being fasterthan the feeding speed of the band sheet A. Side plates are disposed onboth sides of the sandwich conveyor C, and support the end of thepulleys 19 by means of the bearings 21.

A delivery conveyor D is located in front of the sandwich conveyor C andboth ends of each of a plurality of parallel endless belts 22 aresupported by pulleys 23. A shaft 24 of the pulley 23, is located at therear of the conveyor D and is supported by bearings 26 on side plates25. A shaft 27 projects from the center of both ends of the pulley 23and is supported by means of bearings 30 mounted on the upper ends ofpiston rods 29 which are driven by cylinders 28. Thus, the front of thedelivering conveyor D can be moved up and down. The delivering conveyorD is operated at a speed approximately half the feeding speed of theband sheet A. Accordingly, the sheets a on the conveying runs of thedelivering conveyor D overlap. Suction boxes 31 are positioned betweeneach belt 22 in parallel with each other at the front portion of thedelivering conveyor D, the top wall of each suction box 31 beingprovided with numerous small holes 32. The travelling faces of the belts22 are adapted to be located slightly above the top walls of the suctionboxes 31 when the piston rods 29 are in an extended position while thetop walls of the suction boxes 31 project slightly above the travellingfaces of the belts 22 when the piston rods 29 are in a retractedposition. Also, the cylinders 28 are adapted to be operated by at leasttwo kinds of signals from the counter 16, as explained below. An exhaustblower 33 is operated by means of a transmission mechanism 35 of a motor34, a suction port of the exhaust blower 33 communicating with thesuction boxes 31 through a duct 36.

The suction boxes 31 are secured to a supporting member 37 extendingbetween the side plates 25. A supporting plate 38 supports the conveyingruns of the belts 22, and an end of the supporting plate 38 is pivotedin holes 40 in the side plates 25 by pins 39 fixed on both sides of thesupporting plate 38. A shaft member 41 is fixed transversely to theunderside of the rear end portion of the supporting plate 38. Each endof the shaft member 41 is supported by bearings 44 mounted on the upperterminal of a piston rod 43 of a cylinder 42 which is adapted to beoperated synchronously with the cylinder 28. Notches 45 are provided inthe rear edge of the supporting plate 38 to allow the suction box toproject thereabove. Front and rear shafts 46 transverse the belts 22above the suction boxes 31, the ends of the shaft 46 being mountedrotatably on the side plates 25. One end of member 47 is secured to theend of the shaft 46 and the other end thereof is pivoted on upperterminal of the piston rod 49 of cylinder 48,

whereby the shafts 46 can be rotated by means of the cylinder 48.Numeral 50 denotes a leaf spring, one end of which is fixed to the shaft46 and the other ends contacting the conveying runs of the belts 22. Theleaf springs prevent the sheets a running on the belts 22 from floating.The pressure of the leaf spring 50 on the sheets is adjustable by therotation of the shafts 46 accompanied by the clockwise andcounter-clockwise movement of the member 47 by the operation of thepiston rod 49 of the cylinder 48.

Openings 51 are provided in the supporting plate 38 in the middleportion thereof between the belts 22. Tongues 52 are located on theunderside of each opening 51 and one end of each tongue 52 is secured tothe shaft 53 crossing underneath the conveying run of the belts 22. Theends of the shaft 53 are rotatably supported by bearings 54 fixed to theside plates 25. Numeral 55 is a link, one end of which is fixed to theshaft 53 and the other end of which is pivoted on the upper terminal ofa piston rod 57 of cylinder 56 through a pin 58. Accordingly, the otherends of the tongues 52 are adapted to project from the openings 51 byrotation of the shaft 53 accompanied by the extending of the piston rod57, and the action of the cylinder 56 and the cylinder 28 are oppositelysynchronized, such that when the piston rod 57 is extended, the pistonrod 29 is retracted.

A carrying conveyor E is installed in front of the conveyor D. Endlessbelts 62 are entrained in parallel between pulleys 61 (only one of whichis shown) of a shaft 60 whose ends are supported respectively by meansof bearings 59 in the side plates 25. A motor 63 drives the conveyor Dand the conveyor E, a chain 66 being entrained between a sprocket 64 ofthe motor 63 and the sprocket 65 of the shafts 24 and 60.

In the device of the present invention as described hereinbefore, theweb A which is fed towards the cutting means B is cut into sheets a offixed size by means of the cutting edge 13 when passing between therolls 11 and 12 of the cutting means B. The cut sheets a are carriedforwards while being held between the belts 18 of the conveyor C locatedin front of the cutting means. At this time, the number of sheets whichhave passed through is detected by a counter 16 actuated by the actuator17 which is adapted to contact the projecting member 14 once perrevolution of the roll 11 of the cutting means B.

As the sandwich conveyor C moves faster than the delivering speed of theweb A, a space is left between the last of the cut sheets a and thefront end of the band web A. Therefore, a space is left between eachsheet a.

The sheets a are then transfered to the front conveyor D from thesandwich conveyor C and since the delivering conveyor D is operated atapproximately half the speed of the sandwich conveyor C, the sheets a onthe belts 22 of the conveyor D are caused to overlap.

The counter 16 is adapted to generate at least two kinds of signals.When the counter 16 detects a predetermined number of sheets during thecutting operation, the first signal is generated to actuate the cylinder28 to retract the piston rod 29 and at the same time to reset thecounter. After an interval the second signal is generated to actuatecylinder 28 to extend the piston rod 29.

In operation the number of the sheets cut reaches a predetermined numberand the counter detects this occurrence and the first signal isgenerated, The piston rod 29 is retracted by the action of the cylinder28 and the rear ends of the travelling faces of the belts 22 of theconveyor D are lowered. Accordingly, the top walls of the suction boxes31 are caused to project above the conveyint faces of the belts 22. Thusthe sheet a passing on the top wall of each suction box 31 is sucked andhalted thereon and the preceeding sheet a continues towards the conveyorE, while the sheets following the sucked sheet are accumulated thereonand are temporarily held on the suction box. Also, as the piston rod 43of the cylinder 42, which is operated synchronously with the cylinder28, is retracted the end of the supporting plate 38 is lowered toreceive the slack of the belts 22.

The shaft 53 is rotated counter-clockwise by means of the piston rod 57which is elevated by the operation of the cylinder 56, whereby thetongues 52 are projected upwardly through the openings 51. These tonguesprevent the sheets a on the suction box from passing through by anerror.

In the above mentioned .phase, the counter 16 has already started tocount the number of a new batch of sheets in cut sheets and after apredetermined number of sheets is cut, the second signal is generated toactuate the cylinder 28 to elevate the piston rod 29 and as theconveying runs of the belts 22 of the conveyor D are lifted above thetop walls of the suction boxes 31, the sheets a retained thereon arereleased and are again carried towards the conveyor E. At this time, thefront end of the supporting plate 38 is returned to its position by theaction of the cylinder 42, while the tongues 52 are lowered through theopenings 51.

These operations are repeated and successive batches consising of aprescribed number of sheets are obtained.

The present invention has no conventional disadvantages in that no erroroccurs in the number of the sheets constituting a batch, since a sheetcan be positively retained on the suction box and since this arrangementoffers no resistance to the belts of the conveyor, the position ofsheets relative to the suction boxes remains constant.

What I claim is:

l. A device for creating a space in an overlapping stream of sheetswhich are cut from a web to a fixed length which web is fed to thedevice by a conveying means at a fixed feeding rate, comprising:

a counting means for counting the sheets which are cut from the web to afixed length;

a first conveyor for receiving the cut sheets;

a second conveyor having a plurality of parallel conveying runspositioned to receive the sheets from the first conveyor and operatingat a slower rate of speed than the feeding speed of the web to cause thecut sheets to be formed into an overlapping stream;

a suction means positioned between and normally below the conveying runsof the second conveyor;

a plurality of holding tongues positioned between and normally below theconveying runs of the second conveyor and positioned between saidsuction means and said first conveyor, said second conveyor beingadapted to move downward relative to said suction means to cause saidsuction means to project above the conveying runs when the countingmeans reaches a predetermined number, thus adapted to project above andretreat below the conveying runs of said second conveyor synchronouslywith the downward and upward movement of said second conveyor forengaging the front edge of the sheet halted by the suction means so asto prevent the sheet from passing through the suction means.

1. A device for creating a space in an overlapping stream of sheetswhich are cut from a web to a fixed length which web is fed to thedevice by a conveying means at a fixed feeding rate, comprising: acounting means for counting the sheets which are cut from the web to afixed length; a first conveyor for receiving the cut sheets; a secondconveyor having a plurality of parallel conveying runs positioned toreceive the sheets from the first conveyor and operating at a slowerrate of speed than the feeding speed of the web to cause the cut sheetsto be formed into an overlapping stream; a suction means positionedbetween and normally below the conveying runs of the second conveyor; aplurality of holding tongues positioned between and normally below theconveying runs of the second conveyor and positioned between saidsuction means and said first conveyor, said second conveyor beingadapted to move downward relative to said suction means to cause saidsuction means to project above the conveying runs when the countingmeans reaches a predetermined number, thus holding a sheet on thesuction means when said counting means counts a predetermined number ofthe cut sheets and moving upwardly after an interval of time causingsaid suction means to sink below the conveying runs of the secondconveyor and releasing the sheet halted on the suction means and allsheets which were received thereon during the interval of time, saidholding tongues being adapted to project above and retreat below theconveying runs of said second conveyor synchronously with the downwardand upward movement of said second conveyor for engaging the front edgeof the sheet halted by the suction means so as to prevEnt the sheet frompassing through the suction means.